Cutting tool



, S 7. o R 8 1 .Wu w 2, m A w 5 m m E 3 S 3F. W. 4 r 01j EAE s unL /oL 2 MWM PM@ Kr NRM M 5% m md w YF L O .B L H n w. M N .Y N m P. m m F m F o a H m =U. 8, g M. l

Peb, 3, 194. F. P. MILLER CUTTING TOOL Filed May 12, 1944 f 2 Shets-Sheet 2 www@ Patented Feb. 3, 1948 byRobert W.'1homas a exeeutors,l Meadville, Paz; assgnar'to'fnubert W. ThomaaYMeadvili'e; ya.

,The present invention relates to slitting 'lto'ois of theinserted blade type, andmore particularly to animprovement in the means for securing .the

bladesinthetqpllbody. ,In 'the wolsfihe prior artldimclllw .hee .been

experienced. with. hardening the, wel bodyrsuffllently to .withstand the pressui;e and ,frietigonal aotion ,of the bladesecuring or clamping means. has been. found that :the large mass of the material of the tool body :cannot be made vhard enoughto withstand the stress andwar inc-ident 'to the use of alolade clamping met: hards-m.V e.

important objeetof the presentinveIrt-ian isfi'o proviea blade securing means whichwiil n'o't require' .hardening-of the tool body to prevent damage yto the body from the yfunctioning ofthe baldejs'euring means, flirfbbjeot of the invention ,iste `provid'ea s truction. w h1f ch, i s inexpensive to manufacture, fndwhichlis, .stifling ind ecent in use.:

other eleleete ena advantages pf the, inrehtiqn ing descriiition.' ,l

'pa-ijf, -f this ispeeinatiom Flgu're lgisjan elevation df a `tool 'iioldr 'exi/1- "l'o'dyina the present invention, parts 'being shovvh i'nfs'ection': e Y

lii'gureZisa planviewtheiefL Y Figure 3 is a fragmentary 'sectional view taken Figure Bis a -bersiqective 'vievv ofthe "sei receiving ll e The shoe issgbstantially retiraneu'ring unit, 'looking toward the liner;

Figure 6 is a persnective vieW of the clagmpi'xig imit, looking toward the lblade'erig'agin`g fface of "the s'hoe, with the 'look 'screw removed:

rieure 4v"1 le en exploded perspective v-er '-'ieflirter Y modied form -nfthe liner and .shoe.

`.In the drawings, wherein :for the jpnrpose -Ui Y parallels walls. "'wnlrieur :l4 ands, e

the r'ar w'lvl'allt the Ioess :converges inwardly s A et tothe plane of the slt.

a J'stably rnounted in each of 's :its iside removed `from the engage 'serrations I 4' in the "1 5, a shoe Alli, and a tapered te' frljilj -a nel; liln le fieeeived Ain the recess liz, 'thesho'ef being i reed "into engagement with the :g'le f3 by'th'e `action 1of the tapered locking hardened steel Lllavl'ill'g l. l l. .-.Sec'tiom 'and is 'adapted u lvir) t e rebess. )The inner suriae yof 'th'ejline' is sn 1 and junthreaded, and fits lirvd ifq'n li a vepnsta r 1t radius *from endfto "Dplfetjthe inclination of tljie "t e reess 1 2 with respect topthe fladfv ,the curved wall of vthe liner Y. SI' infclnfaition as Will be 'Segu "fA m aninspebtionidf Figure 3. The bottom plane l 'at 'a right angle to the axis n Qrjthe liner, while the rep gi 1 ess v tlzlan a right 'angle 'sjo "of 'tlife'r ar w lfof the r'ess V'and to the periphery iththe `semi-circular groove I8 the 'lesiib is lierjeees'eglz, that le, eeleeteri.v 1 ,e shall 131 threads have a pitch line parallel to the axis of the screw with the tops of the threads turned down or ground oil in increasing amounts as the leading end of the screw is approached to produce a taper on the tops of kthe threads. The threads of the groove I8 are complemental to the threads of the screw. The groove threadsv lead the screw into locking positionY and also keep the screw from falling out when the screw is in a loose'position. The flat tops of the threads of the taper screw engage the smooth surface of the liner and produce a largev area of con Y tact between the screw and liner.-` This gener- `ous bearing area, coupled with the fact that the liner is hardened, will prevent any undue injury lrespect to the plane of the blade to produce the clamping pressure of the shoe against the blade as the screw spreads theshoe out of the liner.

' When the liner, shoe and taper screw are alsvsembled, as in Figures 3, 4 and 5, 'they forma compact integrated unit held together by the colacting knobs 2Q and grooves Ill.V The unit is preferably removably arranged in -the recess I2 and held therein by the snugly tting liner and the tendency for the arms of the liner to spring outwardly against the walls ofthe recess, .but

i. the liner may be permanently secured in the recess by means of brazing, cementing or a peen-.g-y

ing operation, if so desired. AThe construction 4of the clamping unit is simple and `it is eiicient in operation andinexpensive to produce. The

.hardened steel liner mayA be made by a punch press operation at a very nominal c ost. The shoe l -members may be made in pairs on a screw machine or lathe, and subsequently cut' into halves to form two shoes from one piece. l.

The form of invention shown in Figure 9 is the same as the previously described embodiment.

except that each arm of the liner l5' is formed -on its inner face with a pair of vertically spaced knobs or projections 20' which seat in similarly arranged grooves I 9' in the side edges of the shoe tween the liner and shoe.

The invention is illustrated in connection with a serrated blade and slot. A However, it can obviously be used to clamp a plain blade in a plain IB' to provide the interlocking connection beslot because the clamping.`unit'exerts no forces which would tend to disturb the longitudinal or radial positionl of kthe blade.

, The form of the recess in the body is extremely simple, easily produced and not subjected towear.

The combination of the taper threaded screw and so that all pressure is directed toward the blade.

VThe spring liner snugly retains theclamping unit in the recess when the blade isjremoved, but the entire unit may be easily removed `for replacement or other purposes.. The clamping unit ',obtains maximum contact` with the blade relative l'to the size of the recess.

While there is shown and described the pre-- ferred embodiments of the invention, it is to be understood that various changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described the invention, what is maimed is:

1. A device of the character described comprising a substantially U-shaped liner having substantially parallel arms, a shoe member disposed between the arms of the liner and having a groove cooperating with the curved portion oi lthe liner to form a plug receiving bore, and a tapered screw plug in said bore adapted to force the shoe away from the curved portion of the diner, said shoe groove having threads com- Vvsubstantially parallel arms, a shoe member disposed between the arms of the'liner and having a groove cooperating with the curved portion of the liner to form a plug receiving bore, a tapered screw plug in said bore adapted to force the shoe away from the curved portion of the liner, said kshoe groove having threads complementing the threads on the tapered screw plug, said liner comprising a thin, hardened steel member, and projections struck up `from the liner arms on the inner faces thereof, said -shoe having its sides provided with elongated grooves to receive the projections and secure the shoe and liner together while permitting relative movement therebetween.

3. A clamping unit for an insertedcutter blade comprising a substantially U-shaped hardened steel liner, a shoe member bridging the free end portions of the arms of the liner, coacting lmeans on said liner and shoe member lproviding an interlocking slidable connection therebetween, said shoe member having a kgroove cooperating with the curved portion of the liner to form'l a screw receiving bore, a locking screw in said bore .and adapted to force, said shoe away from the curved portion of theliner, the threads on said screw having a pitch line parallel'to the screw axis .and the tops of said threads being progressively 4body at one side of said slot and breaking thereinto, a hardened steel liner snugly and' resiliently `iltted in said Vvrecess and 'being of substantially the same shape assaid recess, the axes of said recess and vliner being inwardly convergent to `the plane of the blade, a shoe member in said recess,

ymeans slidably connecting said Vliner and shoe,

said liner and shoe cooperating to form Ya bore, and an actuating element in said bore for forcing said shoe into binding engagement with said blade.

5. The combination of a tool body provided with a blade slot and a recess adjacent to and open to the blade slot, a blade in said slot, Ya blade clamping unit in said recess comprising a substantially U-shaped member, a. shoe bridging the free end portions of the arms`of said U- shaped member and having a groove cooperating with the curved portion of said memberuto with a blade slot and a recess adjacent to and l open to the blade slot, a blade in said slot, a blade clamping unit in said recess comprising a substantiallyA U-shaped member, a shoe having a groove cooperating with the curved portion of said member to form a bore, an actuating wedge -in said bore and operative to move said shoe away from the curved portion of said member into clamping engagement with said blade, and means slidably connecting said member and shoe.

7. The combination of a tool body provided with a blade slot and a recess adjacent to and open to the blade slot, a blade in said slot, a substantially U-shaped liner in said recess and having substantially parallel arms, a shoe member disposed between the arms of the liner and having a groove cooperating with the curved portion of the liner to form a plug receiving bore, an actuating plug in said bore andadapted to force said shoe away from the curved portion of the liner into clamping engagement with'said blade, and cooperating means on said shoe and liiner providing an interlocking slidable connect on. i

8. The combination of a tool body provided with a blade slot and a recess adjacent to and open to the blade slot, a blade in said slot, a blade securing device in said recess comprising a substantially U-shaped liner having substantially parallel arms, a shoe member disposed between and sldably connected to the arms of the liner and having a groove cooperating withthe curved portion of the liner to form a plug receiving bore, and a tapered screw plug in said bore adapted to force the shoe away from the curved portion of the liner into binding engagement with the blade, said shoe groove having threads complementing the threads on the tapered" 'screw plug.

'9'. The combination of a tool body provided 5 with a blade slot and a recess adjacent to and ,open to the blade slot, a blade in said slot, a blade securing device in said recess comprising a substantially U-shaped liner having substantially parallel arms, a shoe member disposed be tween the arms of the liner and havinga groove cooperating with the curved portion of the liner to form a plug receiving bore, and a tapered screw plug in said bore adapted to force the shoe away from the curved portion of the liner into clamping engagement with the blade, said'shoe groove having threads complementing the threads on the tapered screw plug, and means operatively connecting the liner arms and shoewhile permitting relative sliding movement therebetween.

ROBERT W. THOMAS.

FLORENCE G. MILLER, Eecutors of the Estate of Frank P. Miller, v

Deceased.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS 3 Number Name Date 430,148 Prillwitz June 17, 1890 1,251,140 Van Der Horn Dec. 25, 1917 1,011,107 Blood Dec. 5, 1911 1,190,197 Shimer July 4, 1916 1,681,675 Miller Aug. 21, 1928 1,687,891 Ray Oct. 16, 1928 2,128,571 Miller Aug. 30, 1938 1,756,986 Miller May 6, 1930 o 1,951,100 Miller Mar. 13, 1934 2,209,174 Sheldrick July 23, 1940 2,331,555 Jostich, Jr., et al. Oct. 12, 1943 FOREIGN PATENTS u Number Country Date 543,872 France Sept. 11, 1922 

